Anbernic Win600 Issues

A few versions ago, the Home and Quick Access buttons worked on the Win600 (somewhat. Both acted as the Home button, but would sometimes open Quick Access). However, the volume keys and tapping the power button to sleep didn't. With the latest update, it's now the reverse. Volume keys and tap to sleep works, but neither the Home nor Quick Access buttons work. I've tried with and without firmware overrides. I also tried manually remapping them in Steam's controller settings, but they aren't recognized. Another issue is that the audio device doesn't automatically switch when connected via HDMI. It keeps defaulting to the Win600 speakers, and has to manually be changed every time.